Road, highway detours throughout Seattle Aug. 17-19

Traffic will be diverted in at least three big corridors this weekend as construction crews try to accomplish their summer-street work.

• Boren Avenue in Seattle is closed from Yesler Way to South Jackson Street — cutting the main street route between First Hill and Beacon Hill — until 6 a.m. Monday and again next weekend from 7 p.m. Friday until 6 a.m. Monday.

Workers will be installing electrical lines, setting track, and pouring new concrete for the First Hill Streetcar, to open in 2014.

• Meanwhile, the Celebrate Little Saigon festival is on the corner of 12th Avenue South and South King Street, on Saturday from 2-8 p.m.

• Highway 99 in Sodo has been closed overnight and is supposed to reopen at 8 a.m. Saturday in both directions. Until then, there is no ramp access to and from the high-level West Seattle Bridge. “We know West Seattle drivers and Hempfest fans are counting on Highway 99 this weekend,” said a statement from engineer Hien Trinh of the state Department of Transportation. “To help keep drivers moving, all northbound lanes and the ramps to the West Seattle Bridge will reopen by 8 a.m. Saturday.” But from 8 a.m. to noon on Saturday, Highway 99 will be closed immediately south of Spokane Street, so drivers will detour through the Duwamish area using East Marginal Way. The closures are part of a replacement for the 57-year-old, timber-supported overpass that crosses railroad tracks near Spokane Street.

• Highway 18 east of Auburn is closed during the nighttime hours between midnight to 6 a.m. Saturday, and from 11 p.m. Saturday to 8 a.m. Sunday to repair expansion joints. Traffic will be diverted to Auburn-Black Diamond Road.

• The I-5 express lanes will be closed 8 a.m. to noon Saturday and Sunday, for routine inspection of the Ship Canal Bridge.

• The I-90 express lanes will close Sunday from 4-11 a.m. for the Athleta Iron Girl triathlon.

• The I-5 Corson Avenue ramps are closed in both directions until 5 a.m. Monday, in the last of three weekend shutdowns to repair expansion joints.